trunk/kahadb/src/main/java/org/apache/kahadb/util/Sequence.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.kahadb.util;

/**
 * Represents a range of numbers.
 * 
 * @author chirino
 */
public class Sequence extends LinkedNode<Sequence> {
    long first;
    long last;

    public Sequence(long value) {
        first = last = value;
    }

    public Sequence(long first, long last) {
        this.first = first;
        this.last = last;
    }

    public boolean isAdjacentToLast(long value) {
        return last + 1 == value;
    }

    public boolean isAdjacentToFirst(long value) {
        return first - 1 == value;
    }

    public boolean contains(long value) {
        return first <= value && value <= last;
    }

    public long range() {
        return first == last ? 1 : (last - first) + 1;
    }
    
    @Override
    public String toString() {
        return first == last ? "" + first : first + "-" + last;
    }

    public long getFirst() {
        return first;
    }

    public void setFirst(long first) {
        this.first = first;
    }

    public long getLast() {
        return last;
    }

    public void setLast(long last) {
        this.last = last;
    }
    
    public interface Closure<T extends Throwable> {
        public void execute(long value) throws T;
    }

    public <T extends Throwable> void each(Closure<T> closure) throws T {
        for( long i=first; i<=last; i++ ) {
            closure.execute(i);
        }
    }

}